I say "kinda" because all I'll really talk about is the place and where it is. So if you don't mind hearing about where Percy Jackson winds up going in the book then read on. But if you'd rather find out where he goes by reading the book, then read no further.
MINOR SPOILER ALERT
I'd like to talk about Hephaestus' forge in Mount Saint Helens.
I've grown up pretty close to Mt. St. Helens. Well, relatively close, anyways. We only have to drive a couple of hours to get there. And when there aren't ridges or trees (or clouds) in the way, we can see her from the Portland area. I've also grown up hearing about the history of the volcano, but I honestly don't know if people outside of Oregon and Washington are familiar with it. So I'll tell about the great 1980 eruption, and I would love to hear from my followers whether or not you were already familiar with the history.
About the eighties Mt. St. Helens started doing what volcanoes love to do: getting active. Long story short, the volcanologists said that she would explode to the south, and evacuated a bunch of people south of Mt. St. Helens. After a bit of time the volcanologists decided that nothing was going to happen, and allowed everyone to return home. But guess what? They were totally wrong, and about more than one thing.
Not only did Mt. St. Helens explode, she exploded to the north, not the south as predicted.
It was a disaster, and many people died. But I'm going to be lazy, and rather than try to explain it all myself I'll copy and paste from the Wikipedia article about Mt. St. Helens.
"On March 20, 1980, Mount St. Helens experienced a magnitude 4.2 earthquake.[2] Steam venting started on March 27.[23] By the end of April, the north side of the mountain started to bulge.[24] With little warning, a second earthquake of magnitude 5.1 May 18 triggered a massive collapse of the north face of the mountain. It was the largest known debris avalanche in recorded history. The magma inside of St. Helens burst forth into a large-scale pyroclastic flow that flattened vegetation and buildings over 230 square miles (600 km2). Over 1.5 million metric tons of sulfur dioxide were released into the atmosphere.[25] On the Volcanic Explosivity Index scale, the eruption was rated a five (a Plinian eruption).Now that is one amazing volcano. And because of her recent history I think that Mt. St. Helens is the perfect place for Riordan to have placed Hephaestus' forge, because the ancient monster Typhon is stuck under the volcano. And to quote Hephaestus on the subject:
The collapse of the northern flank of St. Helens mixed with ice, snow, and water to create lahars (volcanic mudflows). The lahars flowed many miles down the Toutle and Cowlitz Rivers, destroying bridges and lumber camps. A total of 3,900,000 cubic yards (3,000,000 m3) of material was transported 17 miles (27 km) south into the Columbia River by the mudflows.[26]
For more than nine hours, a vigorous plume of ash erupted, eventually reaching 12 to 16 miles (20 to 27 km) above sea level.[27] The plume moved eastward at an average speed of 60 miles per hour (100 km/h) with ash reaching Idaho by noon. Ashes from the eruption were found collecting on top of cars and roofs next morning, as far as the city of Edmonton in Alberta, Canada."
"Typhon is trapped, you know. Used to be under Mount Etna, but when we moved to America, his force got pinned under Mount St. Helens instead. Great source of fire, but a bit dangerous. There's always a chance he will escape. Lots of eruptions these days, smouldering all the time" (193.)When I read this I was like "Oh my gosh, this is so perfect!!!" I could tell that Riordan had done his homework. The book was written in 2008, and this beautiful volcano became active again in 2004.
So I guess that the whole point of this post is to say: Good job, Rick Riordan. You did your homework, and it shows. :)